idev0085 / react-boilerplate

0 stars 0 forks source link

slice( ), splice( ), & split( ) methods in JavaScript #108

Open idev0085 opened 2 years ago

idev0085 commented 2 years ago

==============slice( )=================

The slice( ) method copies a given part of an array and returns that copied part as a new array. It doesn’t change the original array.

array.slice(from, until); From: Slice the array starting from an element index Until: Slice the array until another element index For example, I want to slice the first three elements from the array above. Since the first element of an array is always indexed at 0, I start slicing “from”0.

The slice( ) method doesn’t include the last given element.

const myArr = [1,2,3]; const arrTwo = myArr.slice(1,2); console.log(arrTwo);

============== Splice( )=================

The splice( ) method changes an array, by adding or removing elements from it For removing elements, we need to give the index parameter, and the number of elements to be removed: Index is the starting point for removing elements. Elements which have a smaller index number from the given index won’t be removed:

const myArr = [1,2,3]; const arrTwo = myArr.splice(2,1); console.log(arrTwo); console.log(myArr);

Adding Elements For adding elements, we need to give them as the 3rd, 4th, 5th parameter (depends on how many to add) to the splice ( ) method:

array.splice(index, number of elements, element, element);

===========Split ( )================

Divides a string into substrings Returns them in an array Takes 2 parameters, both are optional: string.split(separator, limit) Doesn’t change the original string Can only be used for strings

-------Slice ( )------------

Copies elements from an array Returns them as a new array Doesn’t change the original array Starts slicing from … until given index: array.slice (from, until) Slice doesn’t include “until” index parameter Can be used both for arrays and strings

--------Splice ( )-----------

Used for adding/removing elements from array Returns an array of removed elements Changes the array For adding elements: array.splice (index, number of elements, element) For removing elements: array.splice (index, number of elements) Can only be used for arrays

--------Split ( )----------------]

Divides a string into substrings Returns them in an array Takes 2 parameters, both are optional: string.split(separator, limit) Doesn’t change the original string Can only be used for strings